Plastics exposure harms primate brains

Scientists in the United States report that low doses of the chemical bisphenol A (BPA), widely used in plastic food and drink containers, can harm brain function in primates.

The findings extend earlier research on rats. But experts disagree over whether enough BPA leaches into food and beverages to qualify as an environmental risk.

This new study comes just before a key meeting convened by the US Food and Drug Administration (FDA) about the safety of the chemical in consumer products.

"Our primate model indicates that BPA could negatively affect brain function in humans," researcher Tibor Hajszan said in a statement from the Yale University School of Medicine in New Haven, Connecticut.

Hajszan and colleagues studied continuous exposure to BPA at a daily dose representing the US Environmental Protection Agency's current assessment of a safe daily limit (50 mcg per kilo) in young adult African green monkeys.

Their findings, reported in the Proceedings of the National Academy of Sciences, showed that BPA completely abolished the formation of some nerve connections in two key regions of the brain, the hippocampus and prefrontal cortex.

Hajszan cited "profound implications," given the critical role of these nerve connections in cognition and mood and suggested US authorities consider lowering its estimate of a safe daily dose of BPA for humans.

"This study is the first to demonstrate an adverse effect of BPA on the brain in a nonhuman primate model and further amplifies concerns about the widespread use of BPA in medical equipment, and in food preparation and storage," the researchers said.

Scientists estimate that more than 80% of people tested have measurable BPA in their bloodstream.

In a draft assessment in August, the FDA determined that exposure to trace amounts of bisphenol A (BPA) that leach out of containers into the food they hold doesn't pose a health danger.

Bisphenol A is a synthetic chemical compound found in some hard clear plastics and resins such as food and drink containers, CDs, electronics, and the liners in many metal cans.

US health authorities raised an alarm about BPA in April, stating in a preliminary report that the chemical could cause "neural and behavioral effects in foetuses, infants and children, at current human exposures."

Dozens of studies by government scientists and university researchers had found that BPA usage was a health concern. In April, Canada became the first country to ban the sale of polycarbonate baby bottles containing the chemical.

The US chemical industry and agencies that regulate the use of BPA, however, have deemed the chemical safe.